The present invention pertains to the field of heart valve repair and reconstruction. More particularly, this invention relates to a surgical instrument for holding tissue used in heart valve reconstruction.
For nearly forty years, since the advent of the heart-lung machine, it has been possible to repair and reconstruct diseased heart valves. The concept of repairing, rather than replacing, diseased heart valves began with the work of Professor Ake Senning of Zurich in 1960. (Senning A.: Fascia Lata Replacement of Aortic Valves. Journal Thoracic and Cardiovascular Surgery 54: 465-70 (1967).) However, until recently, methods for reconstructing semilunar valves have generally been characterized by lack of precision and reproducibility.
To overcome these and other disadvantages of the prior methods of valve reconstruction, the inventor of the subject invention developed improved, more easily reproducible, less complicated, and generally standardized, methods of reconstructing heart valves. These methods are generally described in Love U.S. Pat. No. 5,716,399 and Love U.S. Pat. No. 6,129,758, and copending U.S. Application Ser. No. 09/330, 689 of Love, et al. (collectively referred to as the xe2x80x9cLove Patentsxe2x80x9d), each of which is incorporated herein by reference in its entirety. The Love Patents generally describe methods for repairing or reconstructing heart valves preferably using a novel unitary trefoil tissue pattern. An embodiment of these methods can preferably include the steps of (a) sizing of the heart valve based on the distance between adjacent commissures of the native valve annulus; (b) cutting a trefoil tissue pattern corresponding in size to the native valve annulus; (c) temporarily mounting the tissue pattern on a surgical instrument for holding the tissue in a configuration of a heart valve to facilitate attachment of the tissue; and (d) suturing the tissue to the native valve annulus.
The Love Patents disclose an innovative surgical instrument for holding the tissue pattern in a configuration of at least one leaflet of a circulatory system valve. An embodiment of the device described therein is shown in prior art FIG. 1. The instrument generally comprises an upper former 11 having a handle 12, and a lower former 13 having a handle 14. The tissue pattern 15 is placed between upper former 11 and the lower former 13. The formers are brought into complementary engagement by inserting handle 14 into handle 12 and sliding the upper former 11 against the lower former 13. The tissue pattern 15 is held in the configuration of the a closed or partially closed circulatory system valve to allow the tissue pattern 15 to be surgically attached to the native valve annulus.
The present invention relates to a novel variation of a surgical instrument for holding a piece of tissue in a configuration of a circulatory system valve, which provides a number of desirable features not present in the device described in the Love Patents or any other prior devices. The instrument disclosed herein allows the tissue to be surgically attached in an open valve configuration (rather than in the closed or partially closed configuration required by prior devices). The present invention also avoids rubbing of the two tissue forming surfaces so as to reduce the risk of slippage or damage to the tissue when engaging the tissue forming surfaces. In addition, the tissue holding instrument disclosed herein can be manufactured at relatively low cost because it has few parts, which can be manufactured of low-cost plastic materials. The claimed invention provides a new, useful and unique surgical instrument for holding a piece of tissue in a configuration of one or more leaflets of an open circulatory system valve, which provides these and other advantageous features.
The present invention relates to a surgical instrument for holding a piece of tissue in a configuration of at least one leaflet of an open circulatory system valve to facilitate surgical attachment of the tissue. The instrument includes an inner member having a proximal end comprising a handle portion and a distal end comprising an inner tissue holding portion. The inner tissue holding portion has of one or more inner leaves. An outer member is disposed about the inner member. The outer member has an outer tissue holding portion comprising one or more of outer leaves. The inner and outer leaves preferably correspond to the shape of leaflets of a circulatory system valve and may be brought together into complementary engagement with a piece of tissue held between the inner and outer leaves. An actuator, such as a collet, moves the outer leaves radially inward and outward with respect to the inner leaves. The outer leaves are separated from the inner leaves to allow placement of the tissue on the inner leaves. The outer leaves are moved radially inward to hold the tissue between the leaves in a configuration of at least one leaflet of an open circulatory system valve to facilitate surgical attachment to the native valve annulus.
The outer member preferably includes a sleeve slidably disposed about the inner member and one or more arms connecting the outer leaves to the sleeve. The outer member is slid axially toward the proximal end of the inner member to facilitate placement of the tissue on the inner leaves and slid axially toward the distal end to engage the inner and outer leaves.
Each arm is preferably positioned within a groove on the collet that cooperates with the arm to actuate movement of the outer leaves when the collet is slid axially along the arms.
The instrument also preferably includes a tissue loading member. One end of the tissue loading member is engaged with the distal end of the inner member. The other end of the tissue loading member includes a rounded portion for facilitating the placement of the tissue on the inner leaves.
The instrument also preferably includes a locking mechanism for retaining the actuator in place to keep the inner and outer leaves pressed together in complementary engagement, and to prevent linear movement and rotation of the outer member relative to the inner member.
The instrument is preferably provided in a kit comprising a plurality of instruments. Each instrument is one of a predetermined range of sizes corresponding to a range of anatomical sizes of normal human heart valves.